How many medels needed for t9 troop?

For t9 you need approx. 140k medal for a particular type only.

I don't have a number for you, but it is a lot. To unlock T9 troops you need to reach the level 25 in the appropriate training building and also fully complete the research for that troop type. Half of these takes courage medals. To complete the last item in the troop type research tree you also need to have completed the Zone Commemoration and Zone conflict research trees. All of the items in these require medals.

Competing zone commemoration as early as possible will be a big advantage as it will let you earn double medals from the clash of provinces events.